Version 4.13.0

SQLiteCache/WPF/SQLiteCache.WPF.cs

@@ -0,0 +1,251 @@
+// XAML Map Control - https://github.com/ClemensFischer/XAML-Map-Control
+// © 2019 Clemens Fischer
+// Licensed under the Microsoft Public License (Ms-PL)
+
+using System;
+using System.Collections.Generic;
+using System.Data.SQLite;
+using System.Diagnostics;
+using System.IO;
+using System.Linq;
+using System.Runtime.Caching;
+
+namespace MapControl.Caching
+{
+    /// <summary>
+    /// ObjectCache implementation based on SqLite.
+    /// </summary>
+    public partial class SQLiteCache : ObjectCache
+    {
+        public SQLiteCache(string path)
+        {
+            if (string.IsNullOrEmpty(path))
+            {
+                throw new ArgumentException("The parameter path must not be null or empty.");
+            }
+
+            if (string.IsNullOrEmpty(Path.GetExtension(path)))
+            {
+                path = Path.Combine(path, "TileCache.sqlite");
+            }
+
+            connection = Open(Path.GetFullPath(path));
+
+            Clean();
+        }
+
+        public override string Name
+        {
+            get { return string.Empty; }
+        }
+
+        public override DefaultCacheCapabilities DefaultCacheCapabilities
+        {
+            get { return DefaultCacheCapabilities.AbsoluteExpirations | DefaultCacheCapabilities.SlidingExpirations; }
+        }
+
+        public override object this[string key]
+        {
+            get { return Get(key); }
+            set { Set(key, value, null); }
+        }
+
+        protected override IEnumerator<KeyValuePair<string, object>> GetEnumerator()
+        {
+            throw new NotSupportedException("SQLiteCache does not support the ability to enumerate items.");
+        }
+
+        public override CacheEntryChangeMonitor CreateCacheEntryChangeMonitor(IEnumerable<string> keys, string regionName = null)
+        {
+            throw new NotSupportedException("SQLiteCache does not support the ability to create change monitors.");
+        }
+
+        public override long GetCount(string regionName = null)
+        {
+            if (regionName != null)
+            {
+                throw new NotSupportedException("SQLiteCache does not support named regions.");
+            }
+
+            try
+            {
+                using (var command = new SQLiteCommand("select count(*) from items", connection))
+                {
+                    return (long)command.ExecuteScalar();
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine("SQLiteCache.GetCount(): {0}", ex.Message);
+            }
+
+            return 0;
+        }
+
+        public override bool Contains(string key, string regionName = null)
+        {
+            if (regionName != null)
+            {
+                throw new NotSupportedException("SQLiteCache does not support named regions.");
+            }
+
+            if (key == null)
+            {
+                throw new ArgumentNullException("The parameter key must not be null.");
+            }
+
+            try
+            {
+                using (var command = GetItemCommand(key))
+                {
+                    return command.ExecuteReader().Read();
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine("SQLiteCache.Contains(\"{0}\"): {1}", key, ex.Message);
+            }
+
+            return false;
+        }
+
+        public override object Get(string key, string regionName = null)
+        {
+            if (regionName != null)
+            {
+                throw new NotSupportedException("SQLiteCache does not support named regions.");
+            }
+
+            if (key == null)
+            {
+                throw new ArgumentNullException("The parameter key must not be null.");
+            }
+
+            ImageCacheItem imageCacheItem = null;
+
+            try
+            {
+                using (var command = GetItemCommand(key))
+                {
+                    var reader = command.ExecuteReader();
+
+                    if (reader.Read())
+                    {
+                        imageCacheItem = new ImageCacheItem
+                        {
+                            Expiration = new DateTime((long)reader["expiration"]),
+                            Buffer = (byte[])reader["buffer"]
+                        };
+                    }
+                }
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine("SQLiteCache.Get(\"{0}\"): {1}", key, ex.Message);
+            }
+
+            return imageCacheItem;
+        }
+
+        public override CacheItem GetCacheItem(string key, string regionName = null)
+        {
+            var value = Get(key, regionName);
+
+            return value != null ? new CacheItem(key, value) : null;
+        }
+
+        public override IDictionary<string, object> GetValues(IEnumerable<string> keys, string regionName = null)
+        {
+            return keys.ToDictionary(key => key, key => Get(key, regionName));
+        }
+
+        public override void Set(string key, object value, CacheItemPolicy policy, string regionName = null)
+        {
+            if (regionName != null)
+            {
+                throw new NotSupportedException("SQLiteCache does not support named regions.");
+            }
+
+            if (key == null)
+            {
+                throw new ArgumentNullException("The parameter key must not be null.");
+            }
+
+            var imageCacheItem = value as ImageCacheItem;
+
+            if (imageCacheItem == null || imageCacheItem.Buffer == null || imageCacheItem.Buffer.Length == 0)
+            {
+                throw new ArgumentException("The parameter value must be an ImageCacheItem with a non-empty Buffer.");
+            }
+
+            try
+            {
+                using (var command = SetItemCommand(key, imageCacheItem.Expiration, imageCacheItem.Buffer))
+                {
+                    command.ExecuteNonQuery();
+                }
+
+                //Debug.WriteLine("SQLiteCache.Set(\"{0}\"): expires {1}", key, expiration.ToLocalTime());
+            }
+            catch (Exception ex)
+            {
+                Debug.WriteLine("SQLiteCache.Set(\"{0}\"): {1}", key, ex.Message);
+            }
+        }
+
+        public override void Set(string key, object value, DateTimeOffset absoluteExpiration, string regionName = null)
+        {
+            Set(key, value, new CacheItemPolicy { AbsoluteExpiration = absoluteExpiration }, regionName);
+        }
+
+        public override void Set(CacheItem item, CacheItemPolicy policy)
+        {
+            Set(item.Key, item.Value, policy, item.RegionName);
+        }
+
+        public override object AddOrGetExisting(string key, object value, CacheItemPolicy policy, string regionName = null)
+        {
+            var oldValue = Get(key, regionName);
+
+            Set(key, value, policy);
+
+            return oldValue;
+        }
+
+        public override object AddOrGetExisting(string key, object value, DateTimeOffset absoluteExpiration, string regionName = null)
+        {
+            return AddOrGetExisting(key, value, new CacheItemPolicy { AbsoluteExpiration = absoluteExpiration }, regionName);
+        }
+
+        public override CacheItem AddOrGetExisting(CacheItem item, CacheItemPolicy policy)
+        {
+            var oldItem = GetCacheItem(item.Key, item.RegionName);
+
+            Set(item, policy);
+
+            return oldItem;
+        }
+
+        public override object Remove(string key, string regionName = null)
+        {
+            var oldValue = Get(key, regionName);
+
+            if (oldValue != null)
+            {
+                try
+                {
+                    using (var command = RemoveItemCommand(key))
+                    {
+                        command.ExecuteNonQuery();
+                    }
+                }
+                catch (Exception ex)
+                {
+                    Debug.WriteLine("SQLiteCache.Remove(\"{0}\"): {1}", key, ex.Message);
+                }
+            }
+
+            return oldValue;
+        }
+    }
+}